- It happens more frequently within one case
- You mess up throughout several cases on the interview day
- One mistake triggers a chain-reaction of you losing your cool and falling apart in front of the interviewer
To make sure you handle mistakes during case interviews correctly and don’t let them ruin your day, we have compiled the key strategies for you to deal with and recover from your mistakes or errors in a case interview.
Avoid mistakes in the first place
The most efficient strategy is to avoid making the mistake in the first place. Of course, this is obvious but it’s not a platitude. In 80% of the cases, where we have seen candidates mess up. it is the result of them speaking before they think. Many candidates, at some point during the interview, have an epiphany and blurt out a random fact, a wrong conclusion, a statement not based on facts or using untested assumptions, or numerical results after having hastily calculated it mentally. Think before you speak at all times and you will make sure that you are already better than 80% of all candidates.
Sanity check your results and outcomes
A general case interview habit you should adopt is to sanity check results and outcomes. Whenever you get to a new insight, ask yourself ‘does this make sense?’, ‘is it in the right ballpark or completely off (watch your 0s) ?’ Candidates that use this case habit generally perform better than others both in the process (structure, creativity, and business sense) and the product (the recommendation). Also, chances are that you will spot any mistake yourself and correct it in a calm and natural way, leading the interviewer through the process.
Keep your composure
If you happen to make a mistake, keep calm and focused. Carry on confidently. Interviewers also want to see how you deal with setbacks. Therefore, see it as an opportunity. If you don’t make it a big deal out it, the interviewers normally wouldn’t make it a big deal either. One thing we see over and over again: Candidates let one mistake ruin their whole interview. Even if they performed well for 30 minutes and then make a mistake, they completely lose and their performance crashes. Make sure that the mistake does not lead to a chain reaction of you breaking apart in front of the interviewer, Remind yourself that a one-off thing it is not a big deal. Carry on and focus all your mental resources on the next steps.
Interviewers generally want you to succeed. So, if they point out your mistake or probe something you said, you should start going into problem-solving mode about what could be wrong right away. If they start to guide you it is usually because they want you to get back on track. In that case, listen and demonstrate that you are coachable. Show that you are interested in what they have to say and take their feedback into account.
Expect to be pressure-tested
Once you made a mistake in a specific area (e.g., problem structure, pen-and-paper math, etc.) interviewers might probe this area going forward to see if it was an exception or the rule. Hence, expect the area where you made a mistake to become the focus of more attention either in the same interview or in the next round after interviewers have discussed your performance. The more confidence you show, the better you will fare in this pressure test.
How we can help you avoid common pitfalls and make mistakes during case interviews
If you want to improve your case interview and problem-solving skills and learn the key habits and tricks that make you succeed in any McKinsey, BCG, and Bain interview, try our case practice.
Together, we spent 9 years with McKinsey and coached 100s of candidates to receive their desired offers. Our mock interviews have a 100% satisfaction rate and 9 out of 10 candidates that go through our Ready-for-McKinsey coaching program receive the offer. If you want to get the same knowledge in an extensive 40-part video series, check out our Ready-for-McKinsey video academy.
From our experience, most mistakes happen during the math part of the interview. If you want to go deeper to brush up on your math skills, we have created a program with detailed insider learning materials, 25 videos and a guidebook as well as 2,000 practice drills that mimick the McKinsey, BCG, and Bain case interview math as well as the aptitude and analytics test math for you here: the Case Interview Math Mastery.